Comparison of clinical features of type 2 diabetic patients with lada patients in a cross sectional study

Malihe Mohammadi,1,* Seyedeh solmaz moosavi,2

1. Department of biology, Faculty of basic science, University of Sistan and Baluchestan
2. Department of biology, Faculty of basic science, University of Sistan and Baluchestan

Abstract

Introduction

There has been a dramatic increase in the incidence of diabetes in human societies during the past decade. type 2 diabetes is the commonest form of diabetes constituting about 90% of the total diabetic population whereas type 1 diabetes constitutes about 10–15% of the diabetic population. while diabetes is classically divided as type 1 and type 2 diabetes, there are some forms of diabetes which cannot be classified into either of these categories. subgroup of patients diagnosed with type 2 diabetes has circulating antibodies to islet cell autoantibodies (ica) and more frequently to glutamic acid decarboxylase (gada) which distinguishes them from type 2 diabetes. this condition is accompanied by onset of diabetes after 35 years of age and not insulin requiring, at least during the first 6 months after diagnosis. this subset is named latent autoimmune diabetes in adults (lada). epidemiological studies suggest that lada may account for 2–12% of all cases of diabetes. since lada is often misdiagnosed as type 2 diabetes, it must be properly recognized and managed appropriately at the clinical level. in this cross-sectional study, we were looking for to investigate the prevalence of lada by measuring gada and comparison clinical features of gada positive and negative diabetic patients, in torbat-e heydarieh, razavi khorasan province, iran.

Methods

A total of 475 patients (277 females, 198 males) clinically diagnosed as affected by type 2 diabetes as per who criteria, were included in this study. lada patients was identified based on immunology of diabetes society criteria as follows: 1) the presence of type 2 diabetes and age ≥ 35 years; 2) a lack of requirement for insulin at least 6 months after the diagnosis of type 2 diabetes; and 3) serum gada positivity as tested by elisa. demographic data (age, gender, family history of diabetes) were collected from participants at the screening phase. bmi was calculated as weight in kilograms divided by the square of height in meters. in all subjects fasting blood glucose (fbg) was measured by god-pod colorimetric method. c-peptide was determined using commercial elisa kits (ibl, usa). gad antibodies were determined in the above-mentioned groups using isletest gad diagnostic kit (diametra co., italy cat: dko-082). all statistical analyses were performed with statistical package for social science (spss) version 16.0 and p < 0.05 was considered as statistically significant level.

Results

Of 475 patients, 53 ones (11.2%) were gada positive. significance difference was found between gada positive and gada negative patients in mean age (41.62 ± 6.715 vs 53.87 ± 7.739), fbg (154.62 ± 9.46 vs 150.06 ± 12.53), c-peptide levels (0.699 ± 0.27 ng/ml vs 1.37 ± 0.43 ng/ml) and need for insulin therapy to control of disease. there was no significant correlation between these two groups in gender, family history of diabetes and bmi value.

Conclusion

In this study the prevalence rate of lada was 11.2%. mean age of gada positive patients was significantly lower than gada negative subjects (p <0.001). our finding indicated that c-peptide levels are significantly low in autoantibody positive patients than autoantibody negative subjects (p <0.001). this is in agreement with this fact that lada is an autoimmune type of diabetes and progressive β-cell destruction may occur in this case. mean fbg in lada group is significantly more than non lada group (p = 0.011). these data indicated that the severity of the disease is higher in autoantibody positive group than autoantibody negative group. on the other hand, in lada group, 73.6% use insulin for better control of disease, but in type 2 diabetic patients only 21.3% use insulin therapy. although lada patients do not require insulin therapy early in the diagnosis of diabetes, within a few years, β-cell function is severely impaired, leading to insulin dependency in most lada patients. thus measurement of these parameters in type 2 diabetic patient could help physicians to identification and better control and treatment of lada disease.

Keywords

Type 2 diabetes, lada, glutamic acid decarboxylase antibodies